Electric condenser



28, c. w. RICE 1,714,890

' ELECTRIC CONDENSER Filed Feb. 18, 1925 Invenfor: Chester- WRice,

y M1 His Arfohneg.

Patented May 28, 1929.

UNITED smras PATENT oaaicsfl cnnsrnn W. men, or scHnNEcrAnY, New YORK, AssIe-No'n 'ro GENERAL nnno'rnrc COMPANY, a oonroaarrron on NEW YORK ELECTRIC CONDENSER-i Application filed retrial My invention relates to electric condensers, such for example as may be employed between sections of an antenna of the kind disclosed in my copending applications, Ser. No. 7 52,237

a and No. 752,238, filed Nov. 25, 1924: for dlrective radio transmitting systems, assigned to the same assignee as the present application.

'An object of my invention is to provide an improved condenser which may be inserted in 10 an antenna to add capacitance thereto and which shall also function as a strain insulator between the adjacent sections of the antenna,

My invention will be better understood from the following. description taken 1n connection with the accompanying drawing, and its scope will be pointed out in the appended claims. v

In the single figure of the drawing, I have shown two sections land 2 of an antenna conductor suspended as usual above ground and secured to opposite ends of the rod or shaft 3 of insulating material. An example of an insulating material which is well adapted for this purpose is a material formed of mica,

lass and a binder and known as mica-lex, ut any suitable insulating rod may be used; Slidably mounted on the rod 3 are two simllar sheet metal disks 4- each having its periphery turned back to form a stifiening flange 5 and to resent a rounded edge facing the opposite dis in order toprevent a concentration of electrostatic flux, thereby avoiding destructive corona formation at this point. Each disk has its central supporting portion expanded or bulged in the form of a truncated cone 6, which ably united, as for example by soldering, to one'end of a metal sleeve 7 which in turn fits 40 over the insulating-rod 3. By suitable means shown as a-set screw 8, each sleeve and disk maybe secured in any desired position on the rod 3,;the disks being thus held spaced apart the proper distance to give the desired capacitance. Jumpers 9 connect the sleeves 7 with the adjacent sections of the antenna. As shown, each jumperhas one end under the head of a screw 10 and has the other and twisted around the antenna conductor. The antenna conductor sections being secured to the rod 3, the tension of the antenna is taken portion fits over and is prefer 18, 1925. Serial No. 10,112

entirely by the insulating rod. By reason of the conical formation of the central portion of the disks 4, a maximum length of rod 3 is interposed between the two sleeves which are in electrical connection with the antenna conductor. By this construction, the potential gradient along the rod is greatly reduced with a consequent reduction in the dielectric losses and tendency to are over. Relative adjustment of the disks-for tuning purposes is easily made by shifting one or both disks on the rod without mechanical interference with the antenna.

When the desired relative position of'the disks isfound wherein the inductance of'the antenna is substantially neutralized, the disks may be clamped'to the rod and maintained in that position. As so arran ed the mutual capacitance of the two disks because of their close proximity is far greater than their capacitance toground.

What I claim as new and desire to secure by Letters Patent of the United States is 1. A combined condenser and strain insulator comprising a rod of insulating material adapted to be secured to adjacent sections of a conductor, a pair of opposed disks mounted on the rod, said disks having their central portions extending outwardly in opposite directions, and means for securing the disks to the rod at any suitable point along the rod wherebythe disks may be adjusted with respect to each other.

2. A combined condenser and strain insulatorcomprising a rod of insulating material adapted to have its opposite ends secured to sections of an antenna conductor, a pair of opposed disks on said rod, a sleeve secured centrally of each disk and slidably mounted on the rod, and means forsecuring the sleeves to the rod.

3. A condenser comprising an insulating shaft and condenser plates mounted thereon in inductive relation to each other, one of said plates being adjustable on said shaft with respect to the other plate whereby the capacity of the condenser may be adjusted, and means for securing either of said plates in any suitable position along the shaft whereby the plates may be adjusted with respect to each other along the shaft and secured in the adjusted position.

4. A condenser comprising an insulating plates being provided with openings through 10 support and conducting plates thereon, said which the insulator extends, the border of platesbeing provided with openings through each plate being formed so as to stiffen the which the insulator extends, the region of plate and to afi'ect the electrostatic flux along 5 each plate about the opening being bulged the borderof the plates.

for affecting the electrostatic flux about the In witness whereof, I have hereunto set my 15 support. 7 hand this 17th day of February, 1925.

. 5. A condenser comprising an insulating support, and conducting plates thereon, said I I CHESTER W. RICE. 

